Silica distinctively affects cell wall features and lignocellulosic saccharification with large enhancement on biomass production in rice

• Published in: Plant science (Limerick) 2015-10, Vol.239, p.84-91
• Main Authors: Zhang, Jing, Zou, Weihua, Li, Ying, Feng, Yongqing, Zhang, Hui, Wu, Zhiliang, Tu, Yuanyuan, Wang, Yanting, Cai, Xiwen, Peng, Liangcai
• Format: Article
• Language: English
• Subjects: Biofuels - analysis; Biomass; Biomass digestibility; Biomass production; Cell wall; Cell Wall - metabolism; Cell Wall - ultrastructure; Hydroponics; Lignin - metabolism; Microscopy, Electron, Scanning; Mutation; Oryza - physiology; Oryza - ultrastructure; Plant Breeding; Plant Stems - physiology; Plant strength; Rice; Silica; Silicon Dioxide - metabolism
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/j.plantsci.2015.07.014

•Silica is positively correlated with three major wall polymers in 42 rice mutants.•Silica distinctively affects cellulose CrI, Xyl/Ara of xylans, and S-monolignol level.•Silicon supply largely enhances plant height, mechanical strength and biomass productions.•Silicon supplement has dual effects on biomass enzymatic digestibility.•It provides insights into silicon applications on bioenergy crop breeding. Rice is a typical silicon-accumulating crop with enormous biomass residues for biofuels. Silica is a cell wall component, but its effect on the plant cell wall and biomass production remains largely unknown. In this study, a systems biology approach was performed using 42 distinct rice cell wall mutants. We found that silica levels are significantly positively correlated with three major wall polymers, indicating that silica is associated with the cell wall network. Silicon-supplied hydroculture analysis demonstrated that silica distinctively affects cell wall composition and major wall polymer features, including cellulose crystallinity (CrI), arabinose substitution degree (reverse Xyl/Ara) of xylans, and sinapyl alcohol (S) proportion in three typical rice mutants. Notably, the silicon supplement exhibited dual effects on biomass enzymatic digestibility in the mutant and wild type (NPB) after pre-treatments with 1% NaOH and 1% H2SO4. In addition, silicon supply largely enhanced plant height, mechanical strength and straw biomass production, suggesting that silica rescues mutant growth defects. Hence, this study provides potential approaches for silicon applications in biomass process and bioenergy rice breeding.